Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
tinh doi » trinh doc, trinh do, tinh hoc
su sach » so sach, vu sach
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, nang ma
van cau » van dau, van hau, van chat
truc va » thuc va, thuc vat, trung va
va tinh » may tinh
doi cua » dai cua, hoi cua
cua tre » cua te, cuu tre, cua triet

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ty ((nang xa) or (nang cao)) hoi. hieu van cau truc va tinh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ty ((nang xa) OR (nang cao)) hoi. hieu van cau truc va tinh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: su sach ty ((nang xa) or (nang cao)) hoi. hieu van cau truc va tinh doi cua tre*.